A person using a soapy cloth to wash a tire rim on the grass.

Car Washing

Make sure only rain goes down the drain

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Detergent At-home Tips Commercial Carwashes


Detergent in soapy wash water can pollute local waterways. This happens when soap and other chemicals enter a storm drain or stream when you're washing your car. You can help protect the environment by making sure this water does not go into the stormwater system.

At-home Tips

  • Direct wash water toward the lawn or a planted area. 
  • Use half the amount of soap so that the detergent breaks down faster.
  • Keep water out of the street – Wash your car on a driveway or yard. 

Mobile Carwashes

  • Use cool water and biodegradable detergents.
  • Clean vehicles on grass or gravel areas (when possible).
  • Cover nearby storm drains before washing vehicles.
  • Don't do any engine or parts cleaning.
  • Avoid acid-based wheel cleaners. 

Is a mobile carwash coming to your neighborhood? Let us know ahead of time. This will help prevent issues with wash water going into a storm drain. 

Commercial Carwashes

  • Direct soapy water from the carwash to the sanitary sewer system. Don't put wash water in the stormwater system. 
  • If a sewer connection is not available – direct wash water to collection pools or a similar method. Dispose of wash water properly in a sink.
  • Let us know if you see a mobile carwash that isn’t properly disposing wash water. They should follow the same rules as commercial carwashes.



Zachary Poole
Illicit Discharge Coordinator 

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